Inorganic Chemistry

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2 Inorganic Chemistry

3 Inorganic Chemistry

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8 Chapter 1. Introduction to Inorganic Chemistry 1.1 What is Inorganic Chemistry? - organic chemistry: hydrocarbon compounds and their derivatives - inorganic chemistry: everything else including all remaining elements in the periodic table, as well as carbon - research area included in inorganic chemistry 1) organometallic chemistry: bridging organic and inorganic chemistry area 2) bioinorganic chemistry: bridging biochemistry and inorganic chemistry 3) environmental chemistry: including inorganic and organic compounds 4) solid state chemistry: including inorganic and physical chemistry

9 1.2 Contrasts with Organic Chemistry - both: single, double, triple covalent bonds - inorganic chemistry: including direct metal-metal bonds, metal-carbon bond 2014 Pearson Education, Inc. Fig1.1

10 1.2 Contrasts with Organic Chemistry - organic chem.: max. number of bonds b/w two carbons 3 - inorganic chem.: quadruple bonds b/w metals are possible : (1 x σ (sigma), 2 x π (pi), 1 x δ (delta)) : δ is possible due to the d orbital of metal atoms used in bonding (Fig1.2) : even five-fold bond b/w transition metals is reported quintuple (Fig.1.3) 2014 Pearson Education, Inc Pearson Education, Inc. Fig1.2 Fig1.3

11 1.2 Contrasts with Organic Chemistry - H atoms : 1) organic chem.: H bonded to a single carbon 2) inorganic chem.: bridging two or more other atoms ex) in metal cluster compds. bridging across edges or faces of polyhedra of metal atoms - alkyl group: 1) organic chem.: rarely act as bridge 2) inorganic chem.: some examples 2014 Pearson Education, Inc. Fig1.4

12 1.2 Contrasts with Organic Chemistry - coordination number and geometry 1) carbon: maximum coordination number 4 (4 atoms bonded to C, e.g., CH 4 ) 2) inorganic compds: central atom w/ 5,6,7,,, higher coordination number ex) most common coordination geometry for TM: octahedron, e.g., [TiF 6 ] 3- metal atoms - different coordination geometry: 1) 4-coordinated carbon: tetrahedral 2) inorganic chem.: tetrahedral & square-planar 2014 Pearson Education, Inc. Fig1.5

13 1.2 Contrasts with Organic Chemistry - coordination complex: central metal w/ anions or neutral molecules bonded to them through N, O, S - organometaliic complex: metal atoms or ions w/ directly bonded to carbons - tetrahedral geometry: 1) carbon compds.: 4-coordinated compds. (CH 4 ) 2) elemental phosphorous: tetratomic w/o a central atom (P 4 ) 2014 Pearson Education, Inc. Fig1.5

14 1.2 Contrasts with Organic Chemistry - aromatic rings: 1) organic chem.: aryl group sigma bonded to metals 2) inorganic chem.: rings pi-bonded to metals (Fig. 1.6) - metal atom bonded above the center of the ring - metal atoms sandwiched b/w two aromatic rings - multiple-decker sandwiched 2014 Pearson Education, Inc. Fig1.6

15 1.2 Contrasts with Organic Chemistry - Carbon centered metal cluster: C is at the center of a polyhedron of 5, 6, or more surrounding metal atoms 2014 Pearson Education, Inc. Fig1.7

16 1.2 Contrasts with Organic Chemistry - elemental carbon: the past quarter century is the realm of chemistry of elemental carbon. ex) fullerene C 60 ( buckminster fullerene ) interested in applications in fields fullerene compds. as divers as nanoelectronics, carbon nanotube body armor, drug delivery graphene 2014 Pearson Education, Inc. Fig1.8

17 1.2 Contrasts with Organic Chemistry - No sharp dividing lines b/w subfield in chemistry 1) acid-base chem., organometallic chem. also for organic chem. 2) oxidation-reduction reaction, spectra, solubility relations analytical chem. 3) structural determination, spectra, conductivity, theories of bonding physical chem. 4) metal-containing enzyme biochem. 5) organometallic catalysts petroleum & polymer chem.

18 1.6 History of Inorganic Chemistry - Before alchemy era: in the metallic state gold, copper : copper obtained by reduction of malachite (Cu 2 (CO 3 )(OH) 2 ) : Ag, Sn, Sb, Pd 3000 BCE : Fe classical Greece, Mediterranean Sea 1500 BCE : colored glass, ceramic glaze SiO 2 as major component & other metal oxides - Alchemy era: 1) 1 st CE alchemists in China, Egypt,,, - tried to transmute metal into gold - developed distillation, sublimation, crystallization,,, 2) CE alchemists shifted to the Arab and Europe 1150 CE gunpowder in Chinese firework 3) 1600 CE chemistry was beginning to take shape as a science

19 1.6 History of Inorganic Chemistry The Lycurgus Cup (made of glass) - When illuminated from outside, it appears green. However, when Illuminated from within the cup, it glows red. - Red color is due to very small amounts of gold (Au) powder. (about 40 parts per million)

20 1.6 History of Inorganic Chemistry - 17th C: strong acids nitric acid, sulfuric acid, hydrochloric acid - salts (acid + base) - properties of gases - atomic & molecular weight were determined - groundwork for the periodic table : the concept of atoms & molecules Mendeleev & Meyer (periodic table) : the concept of radioactivity by Becquerel : atomic theory including subatomic particles, spectra, electricity (by Bohr) , 1927: quantum mechanics by Schrödinger & Heisenberg

21 1.6 History of Inorganic Chemistry <Inorganic Chemistry> : originally important for mineral sources for qualitative analysis (identify mineral, assess purity and value) - 20 th C: ammonia, nitric acid, sulfuric acid, sodium hydroxide large scale production : coordination chemistry by Werner & Jørgensen : organometallic chemistry - World War Ⅱ: military projects rejuvenated inorganic field Manhattan project (fission bomb, fusion bomb) s: great expansion of inorganic chem s: crystal field theory (describing the spectra of metal ions surrounded by negatively charged ion in crystal) ligand field theory (by molecular orbital theory)

22 1.6 History of Inorganic Chemistry <Inorganic Chemistry> : organometallic catalyst by Ziegler & Natta polymerization of ethylene at lower temp. & press. rapid expansion of this field - biological materials containing metal atoms: model compds. by theoretical work new synthetic technique 2014 Pearson Education, Inc. Fig1.10

23 1.6 History of Inorganic Chemistry <Inorganic Chemistry> - Conversion nitrogen to ammonia: bridging organometallic chem. & bioinorganic chem. N 2 + 3H 2 2NH 3 : reaction requires 400º & 200 atm 15 % yield : bacteria (by nitrogenese enzyme using iron-molybdenum-sulfur protein) RT & 0.8 atm - Medical application: platinum-containing antitumor agents e.g.) cisplatin (Pt(NH 3 )Cl 2 ), satraplatin 2014 Pearson Education, Inc. Fig1.11

24 Chapter 2. Atomic Structure

25 Chapter 2. Atomic Structure The theory of atomic and molecular structure depend on quantum mechanics to describe atoms and molecules in mathematical terms. Fortunately, it is possible to gain a practical understanding of the principles of atomic and molecular structure with only a moderate amount of mathematics rather than the mathematical sophistication involved in quantum mechanics. This chapter presents the fundamentals needed to explain atomic and molecular structures in qualitative or semiquantitative terms.

26 Chapter 2. Atomic Structure Finding of the subatomic particle: Balmer s Equation 원자의 subatomic particle 인전자가 E 를방출하거나 흡수할수있음. Generalized by Niels Bohr 하지만이러한이론은전자의 wave nature 때문에 H 외에는잘맞지않음. 3-D Schrodinger equation 의 solution 이바로 atomic orbitals Schroedinger equation 의 realistic solution 을위한조건들을적용한예 : Particle in a box (1-D) 그래서 wave property 를잘나타내는 equation 사용하기로함 : Schroedinger equation Heisenberg s Uncertainty principle Quantum number 로 AO 표현함. Ψ 표현하는두가지방법 : 1) Cartesian, 2) Spherical QN 의제한으로인해 aufbau principle 필요 : 1) Pauli s 2) Hund s If more than 1 e -, shielding effect: Z Ionization energy, electron affinity, covalent/ ionic radii.

27 2.1.1 The Periodic Table Many Chemists had considered the idea of arranging the elements into a periodic table. But, due to either insufficient data or incomplete classification scheme, it was not done until Mendeleev and Meyer s time. Using similarities in chemical behavior and atomic weight, Mendeleev arranged those families in rows and columns,,, and, he predicted the properties of unknown elements, such as Ga, Sc, Ge, Po.

28 2.1.1 The Periodic Table In the modern periodic table : : periods (horizontal row of elements) : group/family (vertical column) 3 different ways of designations of groups: : IUPAC, American, European 1) American: main group ІA ⅧA; TMs ⅢB ⅧB ⅡB 2) IUPAC: numbering from 1 through 18 for all group 2014 Pearson Education, Inc. Fig2.1

29 2.1.2 Discovery of Subatomic Particles and the Bohr Atoms During the 50 years after the Mendeleev s periodic table was proposed, there had been experimental advances and discoveries as shown in Table Pearson Education, Inc.

30 2.1.2 Discovery of Subatomic Particles and the Bohr Atoms The discovery of atomic spectra showed that each elements emits light of specific energy when excited. : Balmer s equation (1885) energy of visible light emitted by H atom E 1 1 = RH - 2 nh 2 2 n h : integer, with n h >2 R H : Rydberg constant for hydrogen = X 10 7 m -1 = X J * E is related to the wavelength, frequency, and wave number of the light!! hc E = hυ = = hcυ λ h = Planck constant = X Js υ = frequency of the light, in s -1 c = speed of light = x 10 8 ms -1 λ = wavelength of the light, frequently in nm υ = wavenumber of the light, usually in cm -1

31 2.1.2 Discovery of Subatomic Particles and the Bohr Atoms Balmer s equation becomes more general by replacing 2 2 by n 2 l. (n l < n h ) Niels Bohr s quantum theory of the atom : - negative e - in atoms move in circular orbitals around positive nucleus. - e - may absorb or emit light of specific E 2 Z e R = π µ (4 πε ) h E 1 1 = RH n l nh μ = reduced mass of the electron-nucleus combination * m e = mass of the electron m nucleus = mass of the nucleus Z = charge of the nucleus e = electronic charge h = Planck constant n h = quantum number of describing the higher energy state n l = quantum number of describing the lower energy state 4πε 0 = permittivity of a vacuum

32 2.1.2 Discovery of Subatomic Particles and the Bohr Atoms Electron transition among E levels for the hydrogen atom (Fig. 2.2) E release: as e - drops from n h to n l If correct E is absorbed: e - is raised from n l to n h According to Bohr s model and equation, E is inverse-squarely proportional to n. Thus, at small n large E gap at large n small E gap Exercise Pearson Education, Inc. Fig.2.2

33 2.1.2 Discovery of Subatomic Particles and the Bohr Atoms However, Bohr s theory works only for H and fails to atoms w/ more e - because of the wave nature of e -. de Broglie equation: all moving particles have wave properties, which can be expressed as shown below h λ = mυ λ = wavelength of the particle h = Planck constant = X Js m = mass of the particle υ = velocity of the particle e - s wave property is observable due to the very small mass.(1/1836 of the H atom) But, we can not describe the motion of e - w/ the wave property precisely because of Heisenberg s uncertainty principle.

34 2.1.2 Discovery of Subatomic Particles and the Bohr Atoms Heisenberg s Uncertainty Principle Δx Δp x h 4π Δx = uncertainty in the position of the electron Δp x = uncertainty in the momentum of the electron Thus, there is the inherent uncertainty in the location and momentum of e - (Δx is large) (Δp x is small) e - should be treated as wave (due to its uncertainty in location), not simple particles. We can t describe orbits of e -, but can describe orbitals!!! region that describe the probable location of e - electron density Therefore, one should use an equation which describes wave property well!!!

35 2.2 The Schrödinger Equation The Schrödinger equation The equation describes the wave properties of e - in terms of its position, mass, total E and potential E. HΨ = EΨ H = the Hamiltonian operator E = energy of the electron Ψ = the wave function Hamiltonian operator (H) includes derivatives that operate on the wave function. The result is a constant (E) times Ψ.